Simviation Forums

I recently downloaded file l-17 -c and cannot get the Navion to trim. I have even applied full DOWN trim without success. I suspect the problem has to do with pitch MOI; but am not sure of the change necessary.

I'll get it myself and take a look at it.

Auto-pilot??

George, I couldn't find the aircraft you're speaking about. Can you provide more specific information please?

Thanks for your interest!

The file is for a North American Navion - military version l-17a-b.

There is no autopilot involved.

Thanks for your interest!

The file is for a North American Navion - military version l-17a-b.

There is no autopilot involved.

The one on Avsim? I'll D/L that one and take a look.

Wups - probably not that one. That's a Ryan Navion and when I tried it it flies steady as a rock. I'll try again.

Staiduk,

I think he may be referring to Tim Conrad's, 'L-17B-C.zip', at Sim-Outhouse.

http://www.fswarbirds.com/index.php?page=downloadsbak&FileUploadName=Piglet

George,

I tried this one out and found it trimmed out nicely.

Dave

...mmm....I also downloaded this file and couldn't get the nose down even with full down trim and the stick fully forward :-?

I tried just moving the CofG forward with some success but not sure if that was the problem or not..........give it a whirl...at least it is now flyable without any apparent problems.........commoner

Just change this section of the aircraft.cfg to look like this....or any other number you find works.

reference_datum_position = 0, 0, 0
empty_weight_CG_position

Hmmmm, I had no problem trimming Tim's L-17, although the trim indicator had to be slightly 'nose down'.

One thing I did note: Although there is no Autopilot, the autopilot is available in the aircraft.cfg file (autopilot_available = 1). You might try cycling the ap on/off key (Z) 'till you hear the 'ap off' signal, in case the ap is on due to errant Z or carry-over setting. Or edit to; autopilot_available = 0

Dave

Hmmmm, I had no problem trimming Tim's L-17, although the trim indicator had to be slightly 'nose down'.

Just for the record I had no problems either.

Staiduk,

I think he may be referring to Tim Conrad's, 'L-17B-C.zip', at Sim-Outhouse.

http://www.fswarbirds.com/index.php?page=downloadsbak&FileUploadName=Piglet

George,

I tried this one out and found it trimmed out nicely.

Dave

Thanks for the link, Dave.

Well; I checked it out pretty thoroughly. I couldn't find any oscillations at all in a variety of flight conditions; from low-level cruise to screaming powerdive.

Whatever the question, you've gotta check it in a screaming powerdive.  ;D

It's a nice airplane, innit? The graphics are a bit blocky and the .cfg definitely needs work, but it's way better than I could ever do - and it's a nice looking little thing too.

Judging from my tests; I think Dave is bang-on in his assessment. I think it's the latent autopilot that's causing you problems, George. As he said; just go into the CFG and change the autopilot value to 0, and you'll be fine. (I think. Sometimes the autopilot works even with that number at zero. Dunno why - it just does.)

Also as Dave suggests, when you're flying, George; as soon as you feel the nose-up issue you've described, hit the 'Z' key. If the model's latent autopilot is engaged, that will turn it off. You'll hear a high-pitched alarm tone confirming this.

Hope this helps.